How to position a motion sensor

It all depends on how much money you are willing to spend. Obvisly the contractor is pushing some ready to fit diy type security system.

In this case you need to ask him, will the unit allow you to connect to a security company such as ADT/Police via a phone line/ gprs module? as a future option. maybe get him to put a phone wire to the main box ready just to avoid redesigning later. Always good to run 1 6core and a spare 6core in case you want to add more sensors later. Does it have a backup power supply and how often do you have to change the battery and how much will it cost. maybe buy 1 or 2 spare in advance. Will it let you know when the batteries life time is over.(nothing lasts forever)

That was the basic part.

Now thinking of intermidiete planning and costs at a later stage.

Does the unut generally allow you to upgrade to features such as remote access via internet (by purchasing an addon module to the main system), secure/desecure via Bluetooth, module to call another number on alarm trigger like your mobile, your partner (you set your mobile to always have a loud alarm even on silent when the alarm line calls you)

Now thinking of a more hightech and costly solution.

Will the system allow you to include cctv cameras with motion sensing and remote viewing of video via internet.These do not have to be wired- but jammers are easy to buy now a days, and cables are easy to cut--if exposed) Maybe run spare coax cables with power supply in places where you think you might want to have cameras installed and let them lead to the main box in the loft/secret space somewhere.

Ask him what is the make of the system.. and go google it. find a forum see what people have to say about- see if you can find your own prebuilt diy system that might meet your needs and has an option to expand.

If the contractor has no idea what you talking about.. get a specialist security person in to work with your building contractor.. otherwise you might regret it later.

It's surprising not to have a brand name visible, either on keypads or the main system. I will say it is possible that your system is very outdated, and so the alarm company basically doesn't want to touch it (rightfully so), they just want to put in something modern which they know they can support if it breaks.

You should have a control system somewhere. Often these are a metal box that opens and has a circuit board inside. There should be a model number or name on that, and if not, posting a picture would help.

If there is a circuit board like this, it is possible the model/name is printed on the reverse side, as they actually sell the box separately from the circuit board -- the installer mounts it at install time. You'd have to remove the circuit board in order to check this (cut the power, and be careful not to damage the board -- including being careful of static).

Aside from that, there are three general ways to go about fixing the problem.

• Install the missing door sensor

Installing the sensor may or may not be easy. If you have another door sensor, you can verify that you're getting the same thing (usually just a NC magnetic contact sensor, like these):

• Short out the door sensor wire

You may be able to short out the door sensor. There is a very small chance that this won't work, if it requires a resistor to terminate, but that is not common on door circuits. Of course, this door won't be alarmed if you do that. It also means you need to find that wire, somewhere. You could do it at the panel, as well.

• Remove the door sensor circuit

This means re-programming the system to not use this circuit. It definitely requires finding the model, and then figuring out how to program the system. Sometimes this can be done through (at best) cryptic button sequences, other times it needs PC software and a (sometimes special) cable.